Agricultural metering system having multiple sets of meter rollers

ABSTRACT

An agricultural metering system includes multiple independently controllable sets of meter rollers. Each set of meter rollers includes at least one meter roller, each set of meter rollers is configured to rotate about a respective rotational axis, the rotational axes are generally perpendicular to a common plane, and the rotational axes are offset relative to one another in the common plane. The agricultural metering system also includes multiple meter boxes configured to receive agricultural product from a storage tank. Each set of meter rollers is disposed within a respective meter box, and each set of meter rollers is configured to meter the agricultural product from the storage tank. In addition, the agricultural metering system includes multiple distribution lines. Each distribution line is disposed downstream from a respective set of meter rollers and configured to receive the agricultural product output from the respective set of meter rollers.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/868,454, entitled “Variable Geometry Meter Roller”, filed Apr. 23,2013, which is a divisional of U.S. patent application Ser. No.13/071,796, entitled “Variable Geometry Meter Roller”, filed Mar. 25,2011, which is a continuation of U.S. patent application Ser. No.13/045,280, entitled “Variable Geometry Meter Roller”, filed Mar. 10,2011, which are all herein incorporated by reference in their entiretyfor all purposes.

BACKGROUND

The invention relates generally to metering systems and, moreparticularly, to a metering device with variable geometry.

Generally, seeding implements are towed behind a tractor or other workvehicle. These seeding implements typically include one or more groundengaging tools or openers that form a seeding path for seed depositioninto the soil. The openers are used to break the soil to enable seeddeposition. After the seeds are deposited, each opener is followed by apacker wheel that packs the soil on top of the deposited seeds.

In certain configurations, an air cart is used to meter and deliveragricultural product (e.g., seeds, fertilizer, etc.) to ground engagingtools within the seeding implement. Certain air carts include a meteringsystem and air conveyance system configured to deliver meteredquantities of product into an airflow that transfers the product to theopeners. However, the metering system may include meter rollers with alimited ability to control product flow. For example, some meter rollersmay have a uniform geometric shape that does not compensate for a changein product size. With such meter rollers, an undesirable quantity ofproduct may be metered and/or the cross sectional area of the flutes maybe insufficient to meter product having large diameter particles. Thus,an operator will typically replace meter rollers when switching betweenproducts. Consequently, multiple assembly/disassembly steps may beinvolved, thereby decreasing productivity and increasing planting costs.

BRIEF DESCRIPTION

In one embodiment, an agricultural metering device includes a meterroller having a plurality of flutes. An aggregate cross sectional areaof the flutes increases along a longitudinal axis of the meter roller.

In another embodiment, an agricultural metering device includes a meterroller having a plurality of ridges extending between a firstlongitudinal end of the meter roller and a second longitudinal end ofthe meter roller. The metering device also includes a plurality offlutes. Each flute is formed between a pair of adjacent ridges. Themetering device includes a cross sectional area of each flute in a planegenerally parallel to the first and second longitudinal ends whichincreases along a longitudinal axis of the meter roller.

In another embodiment, an agricultural metering device includes a meterroller. The meter roller includes a first longitudinal end, a secondlongitudinal end, and a longitudinal passage extending through the meterroller from the first longitudinal end to the second longitudinal end.The longitudinal passage is configured to receive a drive shaft. Themeter roller also includes a plurality of flutes extending between thefirst and second longitudinal ends. A cross sectional area of each flutein a plane generally parallel to the first and second longitudinal endsincreases along a longitudinal axis of the meter roller.

DRAWINGS

These and other features, aspects, and advantages of the presentinvention will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 is a side view of an air cart having a metering system that mayutilize a variable geometry meter roller;

FIG. 2 is a schematic diagram of an exemplary metering system which maybe employed within the air cart of FIG. 1;

FIG. 3 is a perspective view of an embodiment of a metering system withmeter rollers having a parallel rotational axis;

FIG. 4 is a cross-sectional side view of a meter box of the meteringsystem of FIG. 3;

FIG. 5 is a schematic diagram of another embodiment of a meteringsystem;

FIG. 6 is a top view of an embodiment of a metering system having ameter roller sleeve assembly;

FIG. 7 is a top view of the meter roller sleeve assembly of FIG. 6,illustrating meter roller sleeve adjustment;

FIG. 8 is a perspective view of an embodiment of a meter roller havingvariable geometry flutes;

FIG. 9 is a cross-sectional side view of the meter roller of FIG. 8,taken along line 9-9; and

FIG. 10 is a cross-sectional side view of the meter roller of FIG. 8,taken along line 10-10.

DETAILED DESCRIPTION

FIG. 1 is a side view of an air cart having a metering system that mayutilize a variable geometry meter roller. In the illustrated embodiment,an implement 10 is coupled to an air cart 12 such that the air cart 12towed behind the implement 10 during operation and transport. Theimplement 10 includes a tool frame 14 with a ground engaging tool 16.The ground engaging tool 16 is configured to excavate a trench into thesoil 18 for seed and/or fertilizer deposition. In the illustratedembodiment, the ground engaging tool 16 receives product (e.g., seeds,fertilizer, etc.) from a product distribution header 20 via hose 22extending between the header 20 and the ground engaging tool 16.Although only one ground engaging tool 16, product distribution header20, and hose 22 are employed within the illustrated embodiment, itshould be appreciated that the implement 10 may include additional tools16, headers 20 and/or hoses 22 in alternative embodiments to facilitateproduct delivery to the soil 18. As illustrated, the implement 10includes wheel assemblies 24 which contact the soil surface 18 andenable the implement 10 to be pulled by a tow vehicle.

As previously discussed, the air cart 12 is coupled to the implement 10,and towed behind the implement 10. As will be appreciated, in certainembodiments, the air cart 12 may be towed directly behind a tow vehicle,with the implement 10 towed behind the air cart 12. Likewise, theimplement 10 and the air cart 12 may be part of a single unit, or theimplement 10 and the air cart 12 may be separate units that are coupledtogether.

The air cart 12 includes a storage tank 26, a frame 28, wheels 30, ametering system 32, and an air source 34. The frame 28 includes a towinghitch configured to couple to the implement 10 or tow vehicle. Incertain configurations, the storage tank 26 includes multiplecompartments for storing various flowable particulate materials. Forexample, one compartment may include seeds, and another compartment mayinclude a dry fertilizer. In such configurations, the air cart 12 may beconfigured to deliver both the seeds and fertilizer to the implement 10.Seeds and/or fertilizer within the storage tank 26 are gravity fed intothe metering system 32.

In the present embodiment, the metering system 32 includes sectionedmeter rollers to regulate the flow of material from the storage tank 26into an air flow provided by the air source 34. The air flow thencarries the material through a hose 36 to the implement 10, therebysupplying the ground engagement tool 16 with seeds and/or fertilizer fordeposition within the soil. Although only one hose 36 is included in theillustrated embodiment, additional hoses may be may be employed inalternative embodiments to transfer product from the air cart 12 to theimplement 10.

A control assembly may be communicatively coupled to the metering system32 and the air source 34 to regulate flow of product to the implement10. The control assembly may include a spatial locating device, such asa Global Positioning System (GPS) receiver. In such a configuration, thecontrol assembly will receive geographical position information from theGPS receiver, thereby facilitating position determination of the aircart 12. As such, the control assembly may implement “Smart Farming”whereby the metering system 32 is controlled based on the geographicalposition of the metering system 32, air cart 12, and/or implement 10.

FIG. 2 is a schematic diagram of exemplary metering system which may beemployed within the air cart of FIG. 1. As illustrated, the air source34 is coupled to a conduit 38 configured to enable air 40 to flow pastthe metering system 32. In other embodiments, the conduit 38 may includemultiple conduit sections with one conduit section coupling the airsource 34 to the top of the metering system 32 and another conduitsection coupling the bottom of the metering system 32 to the implement.In such a configuration, air 40 flows through the metering system 32,from top to bottom. The air 40 enters the metering system 32, combineswith the metered product, and exits the metering system 32 as a mixtureof product and air.

The air source 34 may be a pump or blower powered by an electric orhydraulic motor, for example. Flowable particulate material 42 (e.g.,seeds, fertilizer, etc.) within the storage tank 26 flows by gravityinto the metering system 32. The metering system 32 includes a meterroller 44. However, in certain embodiments, more than one meter roller44 may be configured to regulate the flow of material 42 into the airflow 40. In certain embodiments, the metering system 32 may includemultiple meter rollers 44 disposed adjacent to one another along alongitudinal axis of the rollers 44, or in other embodiments, the meterrollers 44 may be positioned so their rotational axes are parallel toone another. For example, certain metering systems 32 include eightmeter rollers 44 arrange in a linear configuration. Such systems 32 areknown as “8-run” metering assemblies. However, alternative embodimentsmay include more or fewer meter rollers 44, e.g., 5, 6, 7, 8, 9, ormore.

Each meter roller 44 includes an interior passage/cavity 46 configuredto receive a shaft that drives the meter roller 44 to rotate. In theillustrated embodiment, the cavity 46 has a hexagonal cross section.However, alternative embodiments may include various other cavityconfigurations (e.g., triangular, square, keyed, splined, etc.). Theshaft is coupled to a drive unit, such as an electric or hydraulicmotor, configured to rotate the meter rollers 44. Alternatively, incertain embodiments, the meter rollers 44 may be coupled to a wheel by agear assembly such that rotation of the wheel drives the meter rollersto rotate. Such a configuration will automatically vary the rotationrate of the meter rollers based on the speed of the air cart.

Each meter roller 44 also includes multiple ridges 48 and flutes 50. Thenumber and geometry of the flutes 50 are particularly configured toaccommodate the material 42 being distributed. The illustratedembodiment includes six flutes 50 and a corresponding number of ridges48. Alternative embodiments may include more or fewer flutes 50 and/orridges 48. For example, the meter roller 44 may include 2, 4, 6, 8, 10,12, 14, 16, 18, 20, or more flutes 50 and/or ridges 48. In addition, thedepth of the flutes 50 and/or the height of the ridges 48 are configuredto accommodate the material 42 within the storage tank 26. For example,a meter roller 44 having deeper flutes 50 and fewer ridges 48 may beemployed for larger seeds, while a meter roller 44 having shallowerflutes 50 and more ridges 48 may be employed for smaller seeds. Otherparameters such as flute pitch (i.e., rotation relative to alongitudinal axis) and flute angle (i.e., rotation relative to a radialaxis) may also be varied in alternative embodiments. Furthermore, incertain embodiments, a meter roller 44 having variable geometry flutes50 may be employed to accommodate a variety of seed sizes.

For a particular meter roller configuration, the rotation rate of themeter roller 44 controls the flow of material 42 into the air stream 40.Specifically, as the meter roller 44 rotates, material is transferredthrough an opening 52 in the metering system 32 into the conduit 38. Thematerial then mixes with air from the air source 34, thereby forming anair/material mixture 54. The mixture then flows to the row units of theimplement 10 via the pneumatic conduits, where the seeds and/orfertilizer are deposited within the soil. In the present embodiment, themetering system 32 may be deactivated by stopping rotation of the meterrollers 44, thereby substantially blocking the flow of material throughthe opening 52. Conversely, the metering system 32 may be activated byengaging rotation of the meter rollers 44. In this manner, product flowto the row units may be temporarily suspending while the ground engagingtools are in a non-working position or when product flow from aparticular meter roller 44 is undesirable.

FIG. 3 is a perspective view of a metering system 32 with meter rollershaving a parallel rotational axis. As illustrated, the metering system32 includes multiple meter boxes 56 positioned adjacent to one another.In this embodiment, eight meter boxes 56 are included in the meteringsystem 32. However, in other embodiments, 1, 2, 3, 4, 5, 6, 7, 8, 9, ormore meter boxes 56 may be employed within the metering system 32. Themeter boxes 56 enable product to flow directly to a meter roller (notshown) disposed inside each meter box. Furthermore, a primarydistribution hose 58 and a secondary distribution hose 60 extend througheach of the meter boxes 56 in a direction generally parallel to therotational axes of the meter rollers. In alternative embodiments, thedistribution hoses 58 and 60 may extend through the meter boxes 56 in adirection generally perpendicular to the rotational axes of the meterrollers.

The distribution hoses 58 and 60 facilitate product flow to the groundengaging tools. In addition, the distribution hoses 58 and 60 enableproduct to be combined or isolated before flowing to the ground engagingtools. For example, product from one or more meter boxes 56 may flowinto the distribution hoses 58, while product from other meter boxes 56may flow into the distribution hoses 60. In certain embodiments, productfrom a separate metering system may be delivered to the hoses 58 and/or60 before the hoses receive product from the meter boxes 56. In thismanner, multiple products may be combined within the hoses 58 and/or 60.

Each of the meter boxes 56 includes a sprocket 62 coupled to the meterroller (not shown). While substantially uniform sprockets 62 areemployed in the illustrated embodiment, it should be noted thatalternative embodiments may utilize sprockets that vary in size and/ornumber of teeth. As such, the rotational speed of each meter roller maybe particularly adjusted by selecting a sprocket having a desired sizeand/or number of teeth. In the illustrated embodiment, the meter rollersare disposed inside the meter boxes 56 and are driven to rotate by thesprockets 62. Further, the meter rollers are positioned so that theirrotational axes are parallel to one another.

In the illustrated embodiment, the metering system 32 includes a drivesprocket 64 and an idler sprocket 66. The drive sprocket 64, the idlersprocket 66, and the sprockets 62 include teeth configured to interfacewith a chain that drives the sprockets 62 to rotate, thereby rotatingthe meter rollers. However, it should be appreciated that a pulley/beltarrangement may be employed in alternative embodiments to drive themeter rollers to rotate. In certain embodiments, the chain may be routedfrom the drive sprocket 64 over the top of an adjacent sprocket 62,under the bottom of a subsequent sprocket 62, and then over the top ofthe next sprocket 62, and so on, along the length of the metering system32. The chain may then extend across the top of the idler sprocket 66,and loop around to the drive sprocket 64. In such a configuration, whenthe drive sprocket 64 is driven to rotate by a drive unit, the chainwill drive each sprocket 62 to rotate a respective meter roller. Thedrive unit may be stopped or started to cause each individual sprocket62 to rotate. Further, a clutch, such as an electrical or a mechanicalclutch, may be positioned between each sprocket 62 and a respectivemeter roller. The clutch may enable each meter roller to be selectivelyengaged or disengaged, thereby enabling individual control of each meterroller. Furthermore, the clutches may be configured to providecontrolled slippage, thereby enabling the meter rollers to operate atvarying speeds relative to one another.

Each of the meter boxes 56 includes a selection bar configured to enableproduct to be distributed into either distribution hose 58 or 60.Furthermore, a tube adjustment bar 68 extends out from the meteringsystem 32 and is configured to control the position of the selectionbars. For example, in one position, the tube adjustment bar 68 enablesproduct metered in the meter boxes 56 to flow into the primarydistribution hoses 58, while in another position, the tube adjustmentbar 68 enables product metered in the meter boxes 56 to flow into thesecondary distribution hoses 60.

FIG. 4 is a cross-sectional side view of a meter box 70 of the meteringsystem of FIG. 3. The meter box 70 includes a roller section 72 and adistribution section 74. Product enters the roller section 72 and isdirected toward the meter roller 44 via a sloped member 76. The meterroller 44 is positioned within an opening 78 in the meter box 70, andthe meter roller 44 is secured in place and driven by a drive shaftinserted through the cavity 46. The drive shaft, in turn, is connectedto the sprocket 62, thereby driving the meter roller 44 to rotate as thesprocket is driven by the chain.

The distribution section 74 includes a tube selection assembly 80 todetermine whether product flows into the primary distribution hose 58 orthe secondary distribution hose 60. The tube selection assembly 80includes a selection bar 82 attached to a hinge 84. Furthermore, thehinge 84 is coupled to the adjustment bar so that movement of theadjustment bar drives the selection bar 82 to rotate in directionsdepicted by arrows 86. When the selection bar 82 is in the illustratedposition, product from the meter roller 44 flows into the primarydistribution hose 58 through an opening 88. When the selection bar 82 isrotated to the left such that the bar contacts the opposite side of thedistribution section housing, product from the meter roller 44 will flowinto the secondary distribution hose 60 through an opening 90. Incertain embodiments, the selection bar 82 may be positioned in a centralposition between the sides of the distribution section housing to enableproduct to flow from the meter roller 44 into both the primarydistribution hose 58 and the secondary distribution hose 60.

As illustrated by arrow 92, product enters the meter box 70 through thetop of the roller section 72. The product is directed to the meterroller 44 via the sloped member 76. As the meter roller 44 rotates,product flows into the distribution section 74. Depending on theposition of the tube selection assembly 80, product will flow to eitheror both of the distribution hoses 58 and 60. Product flowing into to theprimary distribution hose 58 along the direction 94 may combine with anyother product within the primary distribution hose 58, and the combinedproducts will flow toward the implement. Likewise, product that flowsinto the secondary distribution hose 60 along the direction 96 maycombine with any other product within the secondary distribution hose60, and the combined products will flow toward the implement.

FIG. 5 is a schematic diagram of another embodiment of a metering system98. As illustrated, a drive unit 100 is coupled to each meter box 56.The drive units 100 are configured to individually control the rotationof each meter roller. As will be appreciated, the drive units 100 may beany suitable device that may drive the meter rollers to rotate, such asan electric or hydraulic motor, for example. A controller 102 is coupledto the drive units 100 via a wiring assembly 104. The controller 102 isconfigured to send signals to the drive units 100 to selectively engageand disengage rotation of the meter rollers, and to control the speed ofmeter roller rotation. In such a configuration, the meter rollers may beindividually controlled to enable selective meter roller rotation andspeed control.

FIG. 6 is a top view of an embodiment of a metering system having ameter roller sleeve assembly 108. In the illustrated embodiment, meterrollers 44 are disposed within meter roller sleeves 108. The meterroller sleeves 108 are cup shaped or cylindrical, and are configured tosurround at least a portion the meter rollers 44. In certainembodiments, the meter roller sleeves 108 may be configured to surroundan entire meter roller. As discussed in detail below, the meter rollersleeves 108 may assist in controlling the flow rate of product from themeter rollers 44. Furthermore, a sleeve adjustment bar 110 is coupled toeach of the meter roller sleeves 108 via sleeve adjustment assemblies112.

In addition, bar adaptors 114 are coupled to each end of the sleeveadjustment bar 110. The sleeve adjustment bar 110 and/or the baradaptors 114 may be adjusted to cause the sleeves 108 to expose more orless of the surface area of the meter rollers 44. As more of the surfaceof the meter rollers 44 is exposed, a greater amount of product may bedistributed by the meter rollers 44. Conversely, as less of the surfaceof the meter rollers 44 is exposed, a smaller amount of product may bedistributed by the meter rollers 44. Thus, the amount of productdistributed by the meter rollers 44 may be controlled by adjusting theposition of the meter rollers sleeves 108. As depicted, the meter rollersleeves 108 expose a portion of the meter rollers 44 having a length116.

As will be appreciated, certain products may be metered at a low rate,such as canola, for example. Consequently, meter rollers configured todispense such products may be turned at a very slow rate. Unfortunately,hydraulic drive systems configured to rotate the meter rollers may“stall” if turned too slowly. However, in the illustrated embodiment,the sleeves 108 may cover a portion of the meter roller 44, therebyenabling the meter roller to rotate faster, while still metering theappropriate amount of product. The faster turn rate may substantiallyreduce or eliminate the possibility of stalling the hydraulic drivesystem. Other products, such as peas or fertilizer, may utilize a fasterturn rate, so the meter roller sleeves 108 may be positioned to cover asmaller surface area of the meter roller 44. Furthermore, the positionof the meter roller sleeves 108 may be adjusted, either alone or inconjunction with varying the rotational rate of the meter rollers 44, tocontrol product flow rate through the metering system.

The meter roller sleeves 108 may enable a metering system to meter avariety of products with a single meter roller configuration, therebyobviating the process of exchanging meter rollers when switchingproducts. For example, an operator may select a particular meter rollerconfiguration (e.g., having a desired flute depth, number of flutes,etc.) to facilitate accurate metering of a particular product. Theoperator may then remove the current meter roller, and install a newmeter roller having the desired properties. Due to the duration of themeter roller replacement process, the implement will spend less time inthe field, thereby reducing seeding efficiency. In contrast, because theillustrated embodiment facilitates varying product flow rate byadjusting the position of the sleeves 108 and/or the speed of the meterrollers 44, a particular meter roller configuration may be utilized tometer a variety of products, thereby increasing the efficiency ofseeding operations.

In addition to controlling the collective group of meter roller sleeves108, individual meter roller sleeves 108 may be independently adjusted.For example, the sleeve adjustment assembly 112 of a particular meterroller sleeve 108 may be adjusted to cause the meter roller sleeve 108to cover more or less of the corresponding meter roller 44 than theother meter roller sleeves 108. Specifically, each meter roller sleeve108 may be adjusted by rotating the meter roller sleeve 108 about athreaded rod of the sleeve adjustment assembly 112, thereby extending orretracting the sleeve 108. Alternatively, the meter roller sleeve 108may be adjusted by rotating an adjustment bolt of the sleeve adjustmentassembly 112. Such fine tuning may be used to adjust product flow rateto particular groups of row units, thereby compensating for variationsin the number of row units per group.

FIG. 7 is a top view of the meter roller sleeve assembly 106 of FIG. 6,illustrating meter roller sleeve adjustment. As illustrated, the sleeveadjustment bar 110 and/or the bar adaptors 114 are coupled to anactuation unit 118. The actuation unit 118 is configured to move thesleeve adjustment bar 110 and/or the bar adaptors 114 relative to themeter rollers 44. The actuation unit 118 may be operated via hydraulics,a solenoid, an electromechanical device, or any other type of suitabledevice configured to provide the desired actuation. Furthermore, theactuation unit 118 enables the meter roller sleeves 108 to be adjusted(i.e., moved back and forth) during operation, such as while planting orfertilizing a field. Specifically, the sleeve adjustment bar 110 maymove to expose a length 120 of the meter rollers 44. As will beappreciated, the sleeve adjustment bar 110 may be moved automatically,such as via the actuation unit 118, or manually. When the sleeveadjustment bar 110 is moved, each of the sleeves 108 are moved with thebar 110.

Furthermore, the individual sleeves 108 may be adjusted such thatdifferent sleeves 108 cover different portions of the meter rollers 44.For example, one sleeve 108 may be adjusted via an adjustment assembly122, thereby causing the sleeve 108 to expose a portion of the meterroller 44 having a length 124. As illustrated, the length 124 is smallerthan the length 120. However, by adjusting the adjustment assembly 122in an opposite direction, the length 124 may be greater than the length120. Another adjustment assembly 126 may be adjusted to cause the sleeve108 to expose a length 128 of the meter roller 44. The length 128 issmaller than the length 124 and the length 120. However, as previouslydiscussed, the adjustment assembly 126 may be adjusted to cause thelength 128 to be greater than the length 120 and/or the length 124.Further, any of the adjustment assemblies 112 may be adjusted to causethe sleeves 108 to cover a different portion of a respective meterroller 44. Such adjustments may be made manually, or via individualactuation units that may be attached to each meter roller sleeve 108 toindividually fine tune the position of the meter roller sleeves 108.Each meter roller sleeve 108 may also be used to completely blockproduct flow to a respective meter roller 44 by completely covering themeter roller 44. Such a complete product shut off may also be performedby either an actuator controlled or manual controlled arrangement.

As discussed in detail below, the meter roller sleeve assembly 106 mayemploy meter rollers 44 having variable geometry flutes. Such meterrollers 44 may provide increasing displacement along the length of themeter roller 44. Therefore, the product flow rate may vary non-linearlyas the meter roller sleeve 108 covers varying portions of the meterroller 44.

FIG. 8 is a perspective view of a meter roller 130 having variablegeometry flutes. The meter roller 130 includes alternating flutes 132and ridges 134. As illustrated, an aggregate cross sectional area of theflutes increases along a longitudinal axis of the meter roller, therebyproviding a meter roller having a displacement that varies with axialposition. In the illustrated embodiment, each flute twists about thelongitudinal axis as the flute extends between first and secondlongitudinal ends of the meter roller. At a first end 136, the flutes132 have a width 138, while the ridges 134 have a width 140. Further, ata second end 142, the flutes 132 have a width 144, while the ridges 134have a width 146. As illustrated, the width 138 of the flutes 132 at thefirst end 136 is smaller than the width 144 of the flutes 132 at thesecond end 142. Conversely, the width 140 of the ridges 134 at the firstend 136 is greater than the width 146 of the ridges 134 at the secondend 142.

In the illustrated embodiment, an angle 148 between the flutes 132 andthe first end 136 is less than 90 degrees. However, it should beappreciated that in alternative embodiments, the angle 148 may be equalto or greater than 90 degrees. The flutes 132 have a generally arcuateprofile, reaching a depth 150. However, in other embodiments, the fluteprofile may form other shapes, such as square, triangular, circular,etc. Thus, as illustrated, the meter roller 130 has flutes 132 thatexpand in width and depth as they extend from the first end 136 to thesecond end 142. Furthermore, the meter roller 130 has a longitudinalpassage 152 extending between the ends 136 and 142. The passage 152enables a drive shaft to be inserted therein to drive the meter roller130. Although the opening 152 is depicted with a hexagonal shape, anyother shapes may be used, such as triangular, square, pentagonal, etc.,may be employed in alternative embodiments.

As will be appreciated, the illustrated meter roller 130 with variablegeometry flutes may be combined with a meter roller sleeve as describedpreviously. As such, the meter roller sleeve may enable only a portionof the meter roller 130 to meter product. In such a configuration, themeter roller may be adjusted to efficiently deliver various productsizes. Furthermore, a combination of a meter roller sleeve and the meterroller 130 may enable further control of metering properties, such asmetering rates and operating rotations per minute.

FIG. 9 is a cross-sectional side view of the meter roller 130 of FIG. 8,taken along line 9-9. The meter roller 130 has a surface area 154 in aplane generally parallel to the first end. The surface area 154 is thearea of the depicted circular cross-section that excludes the aggregatearea of the flutes 132 (i.e., the collective sum of each individual area156 of the flutes 132), and the area of the passage 152. Furthermore,the area 156 of each flute 132 has a width 158 and a depth 160. Thedepth 160 of each flute 132 varies across the width 158 to create agenerally arcuate shape. It should be noted that the width of each ridge134 is greater than the width 158 of each flute 132.

FIG. 10 is a cross-sectional side view of the meter roller 130 of FIG.8, taken along line 10-10. The meter roller 130 has a surface area 162.The surface area 162 is the area of the depicted circular cross-sectionthat excludes the aggregate area of the flutes 132 (i.e., the collectivesum of each area 164 of the flutes 132), and the area of the passage152. Furthermore, the area 164 of each flute 132 has a width 166 and adepth 168. The depth 168 of each flute 132 varies across the width 166to create a generally arcuate shape. It should be noted that each of theridges 134 has a smaller width than the width 166 of each flute 132.

As will be appreciated, the surface area 162 of the cross-section ofFIG. 10 is smaller than the surface area 154 of the cross-section ofFIG. 9. In addition, the cross-sectional surface area of the meterroller 130 continuously decreases from the first end to the second endof the meter roller 130. Furthermore, it is noted that the aggregatearea of the flutes 132 (i.e., the collective sum of each individual area164 of the flutes 132) of FIG. 10 is greater than the aggregate area ofthe flutes 132 of FIG. 9 (i.e., the collective sum of each individualarea 156 of the flutes 132). As such, the cross-sectional aggregate areaof the flutes 132 continuously increases from the first end to thesecond end of the meter roller 130. Furthermore, the width 166 and thedepth 168 of each flute 132 in FIG. 10 is greater than the width 158 andthe depth 160 of each flute 132 in FIG. 9. Thus, the width and the depthof the flutes 132 continuously increases from the first end to thesecond end of the meter roller 130.

While only certain features of the invention have been illustrated anddescribed herein, many modifications and changes will occur to thoseskilled in the art. It is, therefore, to be understood that the appendedclaims are intended to cover all such modifications and changes as fallwithin the true spirit of the invention.

The invention claimed is:
 1. An agricultural metering system,comprising: a plurality of independently controllable sets of meterrollers, wherein each set of meter rollers of the plurality ofindependently controllable sets of meter rollers comprises at least onemeter roller, each set of meter rollers of the plurality ofindependently controllable sets of meter rollers is configured to rotateabout a respective rotational axis, the rotational axes are generallyperpendicular to a common plane, and the rotational axes are offsetrelative to one another in the common plane; and a plurality of meterboxes configured to receive agricultural product from a storage tank,wherein each set of meter rollers of the plurality of independentlycontrollable sets of meter rollers is disposed within a respective meterbox of the plurality of meter boxes, and each set of meter rollers ofthe plurality of independently controllable sets of meter rollers isconfigured to meter the agricultural product from the storage tank; anda plurality of distribution lines, wherein each distribution line isdisposed downstream from a respective set of meter rollers of theplurality of independently controllable sets of meter rollers andconfigured to receive the agricultural product output from therespective set of meter rollers.
 2. The agricultural metering system ofclaim 1, comprising a drive unit coupled to each set of meter rollers ofthe plurality of independently controllable sets of meter rollers andconfigured to drive the set of meter rollers to rotate.
 3. Theagricultural metering system of claim 2, wherein each drive unitcomprises an electric motor.
 4. The agricultural metering system ofclaim 1, comprising the storage tank having a compartment configured tohold the agricultural product.
 5. The agricultural metering system ofclaim 4, wherein the plurality of independently controllable sets ofmeter rollers are in fluid communication with the compartment.
 6. Theagricultural metering system of claim 4, wherein the plurality ofindependently controllable sets of meter rollers are configured tocontrol output of the agricultural product to a plurality of row units.7. An agricultural metering system, comprising: a storage tankcomprising a compartment configured to hold an agricultural product; aplurality of independently controllable sets of meter rollers in fluidcommunication with the compartment, and configured to control output ofthe agricultural product to a plurality of row units, wherein each setof meter rollers of the plurality of independently controllable sets ofmeter rollers comprises at least one meter roller, each of theindependently controllable sets of meter rollers are configured torotate about a respective rotational axis, the respective rotationalaxes are generally perpendicular to a common plane, and the respectiverotational axes are offset relative to one another in the common plane;and a plurality of meter boxes configured to receive the agriculturalproduct from the compartment, wherein each set of meter rollers isdisposed within a respective meter box of the plurality of meter boxes,and each set of meter rollers of the plurality of independentlycontrollable sets of meter rollers is configured to meter theagricultural product from the compartment; and a plurality ofdistribution lines, wherein each distribution line is disposeddownstream from a respective set of meter rollers of the plurality ofindependently controllable meter rollers and configured to receive theagricultural product output from the respective set of meter rollers. 8.The agricultural metering system of claim 7, comprising a drive unitcoupled to each set of meter rollers of the plurality of independentlycontrollable sets of meter rollers and configured to drive the set ofmeter rollers to rotate.
 9. The agricultural metering system of claim 8,wherein each drive unit comprises an electric motor.
 10. Theagricultural metering system of claim 9, wherein each set of meterrollers of the plurality of independently controllable sets of meterrollers comprises a drive shaft coupled to the electric motor of therespective drive unit.
 11. The agricultural metering system of claim 10,wherein each drive shaft comprises a hexagonal cross section.